1991997

素因数分解:

$3^2\times 7^2\times {\mathrm{4517}}^1$

素因数の和:4537

約数の個数: 18

約数和(自身を含む): 3347838

約数和(自身を除く): 1355841

約数列:

[1, 3, 7, 9, 21, 49, 63, 147, 441, 4517, 13551, 31619, 40653, 94857, 221333, 284571, 663999, 1991997]

約数ペア:

[(1, 1991997), (3, 663999), (7, 284571), (9, 221333), (21, 94857), (49, 40653), (63, 31619), (147, 13551), (441, 4517)]